Science of Water : Concepts and Applications

To the Reader
In reading this text, you are going to spend some time
following a drop of water on its travels.
When you dip a fi nger in a basin of water and lift it up again, you
bring with it a small glistening drop out of the water below and
hold it before you.
Do you have any idea where this drop has been?
What changes it has undergone, during all the long ages water
has lain on and under the face of the Earth?
Running Water. White Oak Canyon Trail, Shenandoah National Forest,
Virginia. [Photo by Revonna M. Bieber (November 29, 2006).]
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